Liquid fuel jet propulsion system



May 2, 1950 l.. A. sKlNNER LIQUID FUEL JET PEoPuLsIoN SYSTEM Filed June 20, 1946 Patented May 2, 1950 LIQUID FUEL JET PROPULSIDN SYSTEM Leslie A. Skinner, Takoma Park, Md. Application June 20, i946, Serial No. 677,944

2 Claims.

(Granted under the act of March 3, 1883, as amended April 30, 1928; 370 0. G. 757) l The invention described herein may be manufactored and used by or for the Government for governmental purposes, without the payment to me of any royalty thereon.

This invention relates to jet .propulsion systems and more particularly to a liquid fuel jet propulsion system for rocket motors.

In the construction and operation of liquid fuel jet propulsion systems for rocket motors, one of the major difficulties has been the release of the fuel, the oxidizing medium and the catalyzing medium to a combustion chamber in the proportions necessary for optimum results. Attempts to provide mechanical means for regulating the pressures of the several supply systems involved so that the .proper proportionality of the mediums used would be maintained throughout the combustion cycle have resulted in complexity of design and construction and invariably in irregularity of operation.

The best method of maintaining the desired proportionality of various mediums to be combined for combustion is obviously by gas pressure. Previously, auxiliary tanks of nitrogen or other inert gas were provided to supply the pressure for operating the system. However, the present invention proposes that the pressure necessary for the operation of the system be supplied directly from the oxidizing medium involved. This pressure will `force the other mediums of the system into combination within a combustion chamber in proportional accordance with the formula calculated for the particular fuel used.

Accordingly it is an object of this invention to provide improved means for injecting into a combustion chamber proportional amounts of the mediums comprising the liquid fuel utilized in a jet propulsion system.

It is a further object of this invention to provide means for operating a liquid fuel jet propul sion system whereby no contact between the oxidizing medium and the liquid fuel occurs until the instant of combustion.

It is a particular object of this invention to simplify a liquid fuel jet propulsion system by eliminating the necessity for the inclusion of nitrogen r other inert gas to provide the pressure for operating the system.

The specific nature of the invention as well as other objects and advantages thereof will clearly appear from a description of a preferred embodiment as shown in the accompanying drawing in which:

Fig. 1 is a schematic diagram of the liquid fuel jet propulsion system of this invention.

Fig. 2 is a cross-sectional view taken along the line 2--2 of Fig. 1.

There is here provided a jet motor 2 having a combustion chamber 3 and a Venturi passage 4 opening rearwardly therefrom. An annular fuel manifold 5 enclrcles the forward portion of combustion chamber 3 and is concentric witha series ofapertures 6 preferably equallyspaced about the periphery of combustion chamber 3; Apertures 6 are so arranged that the fuel enters combustion chamber 3 in the formrof jets meeting at a common point therewithin. Leading into combustion chamber 3 through an opening 2,3 in `the rear end of jet motor 2 is an injectionl nozzle l for the passage of an oxidizing medium, such nozzle 1 so arranged as to provide a jet of oxidizing medium intersecting the radially disposed fuel jets at the common center thereof.,V

A feed line 8 extends from nozzle 1 into an oxidizer supply tank9 4and is provided Awith a shut-off valve IIJ anda pressuref'reducing valve II for regulating the flow of theoxidizing medium of this invention. Oxidizer supplytank 9 is a conventional high-pressurefstorage unit and for the purposes of this invention may contain oxygen, nitrous oxide, nitrogen dioxide or other gas containing a high percentage of readily available oxygen. A first auxiliary pressure linel2 leads from the oxidizer feed line 8 into a fuel storage tank I3.

Fuel storage tank I3 is substantially cylindrical in shape and is provided. with an inlet I4 for .passage of the oxidizing mediumfrom supply tank 9. An outlet I5 oppositely disposed to inlet I4 is provided in fuel.sto'rage tank I3 for receiving a fuel line IIz.` Fuel line I6 leads in turn into the annular fuel manifold 5 on the outside of combustion chamber 3. A control and check valve I1 in fuel line I6 regulates the flow of fuel into manifold 5. Fuel storage tank I3 is provided with a collapsible liner I8 having an outlet therefrom coinciding with fuel tank outlet I5. Between collapsible liner I8 and inlet I4 in fuel tank I3 is an obturating piston I9 arranged to 4actuate progressive collapse of liner I8.

Another tank 20 similar to fuel storage tank I3 but smaller in size contains a liquid catalyzing medium such as an aqueous solution of potassium permanga'nate. This catalyzer tank 20 is pro-l vided with a collapsible liner 2| and ob'turating piston 22 arranged to function in a manner identical with that of the fuel storage tank |31. Catalyzer tank 2|] is, of course, also provided with an inlet 23 for receiving the oxidizingA medium under high pressure from oxidizer supply tank 9 and an outlet 24 from which extends a .feed line 25. Catalyzer feed line 25 extends through an opening 28 in combustion chamber .3 and like the oxidizer and fuel jets, the catalyzer is arranged to be directed at the intersecting center common to all the mediums of the system. A control and checkwalve 2B regulates the flowl of catalyzer medium into combustion chamber `3. A second auxiliary pressure line 21 leads from oxidizer feed line 8 into catalyzer supply tank A2li.

In operation, liner I8 inside fuel storage tank I3 is first lled with the liquid fuelrequired for the operation of this jet propulsion system and then the catalyzer tank 20 is similarly filled with its medium. The check features of control valves I'l and 26 respectively, retain the contents of tanks I3 and 20 until such time as sufficient pressure is obtained from oxidizer supply tank 9. When liners I8 and 2| are lled, obturating pistons I9 and 22 respectively, are seated as shown in the diagram.

By opening shut-oil valve III in oxidizer ieed line I, pressure is admitted from oxidizer tank 9 into tanks I3 and 20 against the respective obturating pistons I9 and 22 therein. 'Since the pressure from the oxidizer supply tank 9 is piped to both tanks I3 and 20 simultaneously, the system will have a balanced pressure throughout. Pressure against obturating pistons I9 and 22 will effect progressive collapse of liners I8 and 2I respectively to force the fuel and catalyzer con' tained therein out through the respective feed lines I6 and 25 into combustion chamber 3 in the form of jets. Valves I I, Il and 26 have apertures (not shown) adapted to provide the desired proportionality in the flow of the mediums involved in this jet propulsion system.

It is obvious that the relative size ofsupply tanks I3 and 20 is dependent on the compositions of the agents stored therein and the combustion formula calculated for the particular mediums used.

Thus there is here provided a simplified method of obtaining optimum combustion of a liquid fuel for a jet propulsion system whereby the pressure necessary to force the several mediums involved into combination is derived directly from one of the combustion mediums.

I claim:

1. A supply system for a jet-propulsion motor comprising in combination, a, fuel-supply tank provided with an inlet and an outlet, a rst coilapsibie liner disposed within said fuel-supply tank and connected to said outlet, a first piston slidably disposed Within said fuel-supply tank between said collapsible liner and said inlet, a fuelfeed line connecting said fuel-supply tank to the jet-propulsion motor, a catalyzer-supply tank provided with an inlet and an outlet, a second collapsible liner disposed Within said catalyzersupply tank and connected to said catalyzer-supply-tank outlet, a second piston slidably disposed within said catalyzer-supply tank between said second collapsible liner and said catalyzersupply-tank inlet, a catalyzer-feed line connecting said catalyzer-supply tank to the jet-propulsion motor, an oxidizer-supply tank adapted to store oxidizer at high pressure, a pressurereducing valve on said oxidizer-supply tank adapted to control the flow of the oxidizer, an oxidizer-feed line connecting said pressure-reducing valve to the jet-propulsion motor, a first pressure-feed line connecting said oxidizer-feed line to said fuel-supply-tank inlet, and a second pressure-feed line connecting said oxidizer-feed line to said catalyzer-supply-tank inlet, all adapted and arranged whereby the pressure in said oxidizer-feed line is transmitted to said fuel-supply tank and to said catalyzer-supply tank to act against said rst and second pistons respectively so as to collapse said respective collapsible liners and thereby provide balanced feeding pressure in all supply tanks.

2. A supply system for a jet propulsion motor having a combustion chamber and a Venturi passage leading rearwardly therefrom, comprising in combination, a fuel-supply tank provided with an inlet and an outlet in opposed axial relation, a first collapsible liner disposed within said fuelsupply tank and connected to said outlet thereof, a first piston slidably disposed within said fuelsupply tank between said first collapsible liner and said fuel tank inlet, a control valve on said fuel tank outlet, an annular manifold disposed around the forward portion of the combustion chamber, a fuel-feed line connecting said fuel supply tank control valve and said annular manifold, said manifold being provided with a series of apertures leading therefrom into the combustion chamber and being disposed so that the liquid fuel injected therethrough will enter the combustion chamber in jets converging to meet at a common point therein, a catalyzer-supply tank provided with an inlet and an outlet in opposed axial relation, a second collapsible liner disposed within said catalyzer tank and connected to said catalyzer-supply tank outlet, a second piston slidably disposed within said catalyzer tank between said second collapsible liner and said catalyzersupply tank inlet, a control valve on said catalyzer-supply tank outlet, a catalyzer injection nozzle obliquely disposed in the forward portion ofthe jet propulsion motor, a catalyzer-feed line connecting said catalyzer tank control valve and said catalyzer injection nozzle, said catalyzer injection nozzle being disposed whereby the catalyzer injected therethrough will meet said converging jets of the liquid fuelsubstantially at the junction thereof, an oxidizer-supply tank adapted for storing an oxidizing medium under high pressure, an oxidizer injection nozzle axially disposed in the forward portion of the jet propulsion motor, an oxidizer-feed line leading from said oxidizer-supply tank to said oxidizer injection nozzle, a shut-olf valve and a pressure-reducing valve secured to said oxidizer-supply tank and adapted to control the flow of oxidizer from said oxidizer-supply tank, a first auxiliary line leading from said oxidizer-feed line to said fuelsupply tank inlet whereby the pressure in said oxidizer-feed line is transmitted to said fuel-supply tank against said lrst piston therein, and a second auxiliary pressure line leading from said oxidizer-feed line to said catalyzer-supply tank inlet whereby the pressure in said oxidizer-feed line is transmitted to said catalyzer supply tank against said second piston therein, all adapted and arranged whereby the pressure maintained in said oxidizer-feed line is communicated to said fuel-supply tank and to said catalyzer-supply tank thereby providing balanced feeding pres- -sure in all said feed lines and maintaining pro- K portional equivalence of ilow therethrough.

LESLIE A. SKINNER.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 1,207,333 Shonnard Dec. 5, 1916 1,211,104 Dieter Jan. 2, 1917 1,232,247 Dow July 3, 1917 1,382,769 Ferguson June 28, 1921 2,402,826 Lubbock June 25, 1946 '2,406,926 Summerfield Sept. 3, 1946 2,470,564 Lawrence May 17, 1949 OTHER REFERENCES Astronautics," Journal of the American Rocket Society, No. 34, June 1936, pages 9 and 10. 

